The Most Power You’ll Ever Be Able To Fit In Your Pocket : 6Ah 3.3 lb 30Q Luna Mighty Mini Cube Pack Reviewed

Not even a year ago I would throw my huge 12Ah 16lb LifePo4 Prismatic battery in my backpack and head out to ride in the woods for an hour or two. Although I had experimented with the ultra-light Hobby King Lipo’s they simply had too many downsides to feel safe strapping one on my back to go riding in the woods. Over the last few years, the 18650 cells have improved dramatically to the point where, in my opinion, it is really the only kind of packs you would want to consider for an ebike.

The Luna Mighty Mini Cube is unlike anything else you will find on the ebike battery market today.

Many months ago I was lamenting to Eric from Lunacycle about how he should build a small ‘spare tank’ battery for ebikes. This battery would have around 5Ah of range or so and would be small enough to keep in your pocket for when your main pack died. This project was already well underway in the Lunacycle skunkworks and after many months of testing the packs are finally here. These packs are currently sold in three different configurations.

Although the BMS for these Mighty Mini Cubes is capable of putting out 30Amps Cont, I list what I would recommend running these packs at, as the cells are not really capable of putting out more than that amount of power for anything more than a short period of time without getting much hotter than I think they should get.

I have to say it’s an amazing feeling to just throw one of these batteries in your backpack and go for a ride without even being able to feel the weight of the battery at all. I tested the 30Q pack pretty extensively on singletrack and I have to say that this pack surpassed my every expectation. Before these Mighty Mini 2P packs came out your only option for using a 2P pack was to rewire a power tool battery pack or make your own out of higher power cells like the 25R. The new 18650 cells for 2016 can provide BOTH high power AND high-capacity allowing these new 2P packs to arrive and impress us all with their power capacity and peak output ability.

Is that an ebike battery in your pocket, or are you just happy to see me? I wear socks so that other people aren’t tortured by looking at my toes.

I bought one of these batteries as soon as it hit the market and anxiously waited for it to arrive. The shipping cost was only $30 (most of the bigger batteries have a fixed shipping cost of $40) and when it arrived I charged it to full capacity using my 52v Lunagizer charger which is the only charger I recommend other than the Cycle Satiator. I decided that I would see how long it lasted with a BBS02 using PAS only at power level 2. For my first ride after about 40 minutes the battery still seemed to have plenty of juice in it and it wasn’t even warm yet so I laid on the throttle. After about 10 more minutes of riding at full throttle, the battery had gotten warm, but the Mighty Mini cube still had a charge and was still putting out plenty of power. This is one of my favorite parts of using 52v 14S batteries on drive systems like the BBS02 and BBSHD which were designed for only 48v systems. The 52v systems run the drive unit at nearly full power even when they are close to dying. With a 48v 13S pack once it gets near the end of its charge the battery starts feeling really anemic.

The Mighty Mini Cube weighs in at only about 3.3 lbs

I tested the Mighty Mini in my pocket, but it was pretty uncomfortable, it felt like I was carrying around a small brick. The best setup I found for this battery was dangling from under the seat using a Saddle Bag Scrotal Sack. The battery fit nicely and since it was dangling down it didn’t hit against the bottom of the seat or seat tube. As an added bonus this is one of the stealthiest places to store your battery as no one is going to look under your ass when they ride by you, nor are they going to suspect that your battery is so tiny that it will fit in a saddle bag sack.

One of the biggest barriers for people getting into the ebike market is the cost of the battery system. When I’m commuting on the road with a BBS02 and a 52v battery I get about 1.5 miles per amp hour at the highest level of pedal assist with a 52T front ring. This means that most people can average about 25mph on their ebike and with the PF pack should be able to go over 10 miles per charge with a $229 battery that weighs in at only 3.3 lbs. What we are seeing here is nothing short of revolutionary as the price\weight\performance characteristics of ebikes are now breaking into what normal consumers (not just enthusiasts) are willing to accept. While I didn’t think much about strapping a 16lb battery to my back to go riding in the woods for an hour or two, most normal people would think I am totally insane. Let’s face it, backpack batteries suck.

A cheap way to hide your battery somewhere people are not likely to look, under your bum.

A note about power and heat. I have found that when I run the BBS02 with PAS at power level 9 it hovers between 15 and 20Amps of power. If you have a BBS02 and want to use the throttle then the only 2P pack you should even consider getting is the 30Q. If you are happy using PAS only then the GA or PF packs should be fine. If you have a BBSHD then the only pack that I recommend you consider getting is the 30Q pack, as the GA and PF packs will overheat if you run the BBSHD at the higher power levels or lean on the throttle. Although I really like the GA cells (52v GA Shark pack review is coming soon) they do tend to get pretty hot at high-current draw, at least hot enough so that it makes me pretty nervous. If your hub motored ebike has a controller that is between 20 and 30Amps then I would go for a 30Q pack only. If your controller is 20 Amps or less then the GA or the PF packs will both work well, just pick the most expensive pack that you can’t afford. That is what other people’s credit cards are for.

Remember that most but not all 48v ebike controllers can run with 52v packs. The best way to test to see if yours will work is to plug someone elses 52v battery fresh off the charger to your controller and see if it works of if there is a high voltage cutoff. If there is no high voltage cutoff then it will probably work, although it will certainly void any warranty you have and you could fry your controller. You only live once.

Just make sure that the bike seat pack will fit your battery before you buy it.

If you’re looking for an ultralight battery pack for single-track riding in the woods, banging around town in, or as a spare tank of juice for when your main battery dies, then look no further than the Luna Mighty Mini 3.3lb 52v 14S2P Cube. There is nothing else like it on the market and I can say that this pack delivers on all the promises that it makes for weight, performance, and fun.

Hey Karl. What do you think of batteries from other companies, like Grin? Are there other companies that sell similar quality batteries like Luna? This new little pack seems great, although the idea of buying a $300 battery on top of a $600 long range battery raises the investment by a lot. Not sure my banker will approve both batts.

I have not used the Grin batteries. I have bought a bunch of batteries direct from China & from Hobby King and not had good luck with them. So far (knock on wood) my Luna batteries have been pretty good.

Hi Karl, nice review. What is the smaller XT60 connector for? It’s not stated on the Luna product page. They mention the spare female is for the controller, but there’s only a loose XT90 male pictured, and the XT60 male to battery.
Since I’ve had a short circuit KFF incident off battery supply with the male connectors and multimeter probe, I’m very wary now of the default safety convention of power being female connector. Even off an RC charger it’s possible to pull the banana plugs first/easier than the harder to pull XT90 while it’s still on battery, easily can become banana history. Don’t do the kids 9V battery trick and get your friend to stick their tongue across the terminals =P

It’s interesting the pack size is 1/3rd of my lunchbox container with the HK Multistar 6S 16Ah 42-50V LiPo pack that with container is same 6 x 3.25 inches width/height but triple length at 9 inches with foam padding and wiring room. I could fit 3 of the 30Q packs for BBSHD and get 18Ah in the similar volume without the container, with higher voltage and longer life. I’ve just got to say my vows and commit to one kit or battery configuration beyond more than testing mileage, but I feel I’m stabilising with 2 pedal fat bikes and 1 BBSHD fat bike and 1 guest fat bike. With 16Ah pedelec and throttle only for tricky situations I still only use under 4Ah of the 16Ah pack on a typical local recreational ride while testing so far (don’t commute), so I can relate to Luna’s scenario for using and making this size. The issue with commitment is the bike’s test goal to get me beyond my local pedal range recreational radius, to see things in a day trip just beyond normal range, still desires long range maximum capacity. As the rare “holiday time” scenario though it’s expensive and prohibitive compared to the hours of use it would get. Nice problems to have I suppose.

The XT60 is a charging connector. I’m also not crazy about having a male plug off the battery for the same reasons you mention, but that is the standard that Luna has settled on.

I find it is better to have a couple small batteries than one big battery as you can switch them around easily as you need them and when I’m in town I can leave a battery to charge while I go out and ride around on the other battery. I can take only what I need when I walk out the door. Most people bring way more range (double or triple) when they walk out the door than what they actually need.

I am confused and worried about battery safety. On one hand, people say to never leave a battery alone when charging. Now you are saying you leave a battery on charge while you go out. I plan on charging batteries in a ammo box and storing them in another ammo box. But what is the bottom line in battery safety and strategies? Build a layer of cinder block on the garage floor and then put the batts in a ammo box? Does the charger go in the ammo box too, or can it sit on a cinder block? Or should they not be in the garage at all, but on the patio. I can’t see leaving them in the house, as that seems to be the worst idea! Even if you don’t get fire, you get toxic smoke.

The $229 is a grabber price for new builders and basic hubs. A 36v version might be less confusing and could be adapted to the older bikes with batteries that are starting to fail. I have the 30q version and it’s a great size. Too bad the GA isn’t quite the match for the 30q. Luna is a real battery franchise. I use LiPo and Lifepos, but two Mini 30’s would be a great way to go. I don’t think there is much of a penalty for not paralleling them, if you have two. You lose a bit of capacity at high discharge, if vapers can be trusted.

Never hook together any Lithium batteries in parrellel unless you are pretty sure they are about the same voltage. If one is fully charged and the other is drained the power will rush from one battery to the other and could cause very serious problems. I don’t connect batteries in parallel unless they are within .2 v of each other. (That’s a decimal place in front of the 2)

About a year ago, I asked them the same question (before this battery came out). Eric was very helpful, but had no interest in making a 36v battery. He likes the 52v stuff, and thought there would be no market for 36v.

I asked Paul at em3ev the same question. He soured some higher powered cells than he had at the time, and eventually built me the same size pack (with the 30Q cells), but in 36v. The advantage is that I have a 3lb pack that can take me at 25mph and 25 miles. That has been my holy grail for years, and as of 2016 it is my daily ride on a fast light road bike.

Eric and Paul are both great, and I love that Paul will build me a custom pack to match my needs (10s3p). I think next season I’ll build a 10s2p pack so I’ll have a choice of batteries, and extended range. Like Karl said, it is nice to have choices, rather than hauling around the biggest battery you can afford everytime you roll down the road.

“The advantage is that I have a 3lb pack that can take me at 25mph and 25 miles. That has been my holy grail for years, and as of 2016 it is my daily ride on a fast light road bike.”

A 30 cell 30Q pack provides 300Wh at a 1C rate (25 miles @ 25 mph) or 300W average. 25 miles and 300Wh is 12 Wh/mile. If you can do this on a “fast light road bike” you are the first ever. No one goes 25 mph @ 12 Wh/mile, it requires closer to twice that. Perhaps you could do it by adding 300W continuous of your own but who does that and rides regularly on an e-bike? Perhaps you meant to say 25 miles @ 15 mph with a max speed of 25 (which is quite high for a 36V pack as well).

30 30Q cells also weighs 3.2 pounds without anything else comprising a pack. I’d suspect your pack is 20% heavier than you claim. Glad you are happy with your solution but your claims are exaggerated.

I understand the skepticism. I said the same thing about the Sondor’s ebike when it first hit kick starter. Turns out his initial videos were of a 3500-watt bike, not a 350 watt bike. I agree with healthy skepticism.

“Perhaps you could do it by adding 300W continuous of your own but who does that and rides regularly on an e-bike?”
I dunno, 60 minutes said Lance Armstrong did it! 😉

You are right. I’m not normal, LOL. I designed my bike to double my power. ~250watt legs + ~300 watt electric on a drop bar race bike is a fast bike. Yesterday I did 27+mph for over a mile on my commute home, but my typical cruising speed is between 24 to 25mph. 25 miles is about as far as I would go, but that is hasn’t hit the LCV cut off yet. I have over a year’s worth of Strava data documentation on this setup.

I’m still confused about the various battery types. Luna Cycle lists a PF, an NCRB and a GA. Is the NCRB the same as the 30Q you refer to in the above article or is this a fourth type? Could you compare the different types and list the benefits/drawbacks of each type?

I’m planning on buying a Bafang BBSHD kit. Luna Cycle says that the Panasonic PF Cell is recommended If you do “a lot of off roading at full power” or hill climbing, but you said that the PF will overheat if run at higher power levels or with lean throttle. Mmmm? You meant to say, “higher power levels or HEAVY on the throttle”, right? Mmmm! If I run it at lower power levels (under what level?), could I get away with a PF or GA? If i could get away with any of those battery chemistries by using appropriate power levels, then which type would you recommend using with the BBSHD?

Perhaps you’ve already written an article comparing these battery types. If so, please give us the link. I can’t find it. Many thanks Karl!

And what are the differences between the PF and GA? Range or power difference? I’m sorry, I don’t know what 2P means.

The LARGER shark batteries that are sold with the BBSHD are either the PF or GA. I don’t have an option to purchase a 30Q in those sizes. So, my only options to power the BBSHD with power modes above 5 are the mighty minis?

2P means there is 2 parallel groupings of cells. The PF and GA both support 10Amps cont, The GA has more capacity than the PF but is more expensive. I really like the GA cells, it is my favorite right now.

God, this is all so confusing. Why is the 30Q the best battery of the group? Even Luna does not adequately explain their products. You’d think they would have articles as to why one would choose one over the other. Sigh.

You guys need an intern to provide product info on your stuff, very confusing and complicated and i am a former engineer! I love my new luna bbshd and shark GA 52v and fancy charger but still dont know what voltage it SHOULD charge to (shuts off at 54 volts) or what voltage it shuts off at discharge on the bike (i use 80% ). F it all I am just having fun with it now pulling around my 3 and 7 year old in vermont! Ill ask questions next winter!

How is it a good idea to suggest that a 2P pack made from 30Q cells is good for 30A continuous? You are even suggesting that it is ok to run 2P of PF or GA cells are ok with a 30A BBSHD, so long as you use a PAS of level 5 or less.

If you run a 2P on a GA or PF pack with a 30 amp BBSHD then you can’t really use the throttle but you can use up to PAS level 5 out of 9. If you have only 5 PAS levels then you shouldn’t go over PAS level 3. These packs work just fine as a ‘spare tank’ if you’re not feeding them full juice and are just trying to get home after your main pack is dead. You are correct that it is stupid to run a 2P pf or GA pack at more than 20 amps because that is what the cells are rated at. If you can’t restrain yourself then you should buy a 30q. I think the article is pretty clear on that point. Thanks for your concern.

So if I buy 2 of these mini packs, will it be enough for say 30 miles of mtn bike offroad? One of the trails is only 13 miles but has 2300 feet of climbing. Id like to use 1 for the pack under the saddle and keep a spare on my backpack.

If somebody was going to use one of these 52v mini batteries with a Smart Pie Hub motor like Luna sells, are there any specific benefits or downsides of using one over the other? For example, GA pack is 7 ah, so presumably would yield a little more range, yes? Any other variables to consider?